Effects of L-carnitine in the Gestating Sow Diet on Fetal Muscle Development and Carcass Characteristics of the Offspring

Abstract

Musser, R.E., Dritz, S.S., Davis, D.L., Tokach, M.D., Nelssen, J.L., Goodband, R.D. and Owen, K.Q. 2007. Effects of L-carnitine in the gestating sow diet on fetal muscle development and carcass characteristics of the offspring. J. Appl. Anim. Res., 31: 105–111. A total of 232 sows were used to determine the effects none or an additional 50 ppm of L-carnitine in the gestation diet on sow and offspring performance. Sows were fed dietary treatments from breeding until d 110 of gestation. Offspring from sows were ear-notched according to maternal treatment at birth and carcass data were obtained at slaughter. Sow plasma IGF-I concentration was similar (P>0.10) between control and L-carnitine supplemented sows on d 30 and 60 of gestation at 2 h after feeding. No differences were observed in either the immediate or subsequent number of pigs born per litter. No differences were observed in a sub-sample (n = 181) of pig weight at birth, weaning or d 59 of age between control and treatment offspring. Analysis of newborn pigs revealed no differences in semitendinosus cross-sectional area or primary (slow-twitch, red) fibers. Offspring of sows fed L-carnitine had a numerical tendency (P = 0.11) for a lower ratio of secondary:primary fibers compared with offspring of control sows. No differences were observed in hot carcass weight (87.6 kg); however, loin depth (57.0 < vs 59.4 mm; P < 0.01) and percentage lean (54.45 vs 55.10; P < 0.01) were increased, and backfat decreased (18.4 vs 17.8 mm: P < 0.01) in offspring of sows fed L-carnitine during gestation. Therefore, while feeding L-carnitine during gestation had no effect on the number of pigs born, it improved carcass leanness of the offspring at market weight and tended to lower ratio of secondary.—primary fibers at birth.